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Marine RenewablesMarine Renewables

Offshore wind

Ocean energy is not just in the water. There’s offshore wind, which tends to be steadier than onshore wind. But turbines are harder to build and maintain in a marine environment than they are on land. The Bureau of Ocean Energy

Management (BOEM) estimates theoretical US offshore wind potential is four times current US power output, although practical recoverable power will be smaller.

Entrepreneurs have taken notice. One company, Boston- based Energy Management, plans to start building what likely will be the frst US offshore wind farm later this year. The 2 company envisions a 130-turbine, 468MW capacity, 65km facility in Nantucket Sound and already has pre-sold three- fourths of the power.

Other companies are waiting in line, and the US

Department of Energy is trying to help with challenges that include stiffer permitting requirements and higher capital and operating costs than onshore wind operations. DOE recently awarded grants to seven projects on the

Atlantic, Gulf and Pacifc coasts. Among them is

Seattle-based Principle Power’s plan to build a truly oceanic wind machine, a foater that does not have to anchor on the bottom in coastal waters like virtually all its predecessors pictured above right is a prototype which has been operating ( ).

offshore Portugal since October 2011 As with wave and tidal energy, the UK is the world leader.

The world’s largest offshore wind farm, the London Array, is in the outer Thames Estuary. It was declared fnished UK power demand, by 2020. Cost estimates have not been in December 2012 upon installation of the 175th turbine disclosed. pictured below ( ). The London Array started generating power Dogger Bank is being developed by Forewind, a consortium last October and is due to be running at maximum capacity of UK-based SSE, Norway-based Statkraft and Statoil, and of 630MW – enough for 470,000 homes – this spring. RWE npower renewables – the UK subsidiary of the German The London Array was built by UK-based E.On, Abu Dhabi’s renewable energy company RWE Innogy.

Masdar and DONG Energy, based in Denmark, the nation that “There’s a lot of public support for renewable energy in pioneered offshore wind in 1991. the UK and for offshore wind in particular,” says Lee Clarke, An even larger UK offshore wind project, Dogger Bank, is Forewind director and general manager. “The UK government being developed in the North Sea, off the coast of Yorkshire. has really got behind fnding ways to exploit this fast

The ultimate goal is huge, 9.6GW, equal to nearly 10% of renewable energy source off our coasts.” oedigital.com oedigital.com February 2013 | OEFebruary 2013 | OE 4343 oe_renewables.indd 43 31/01/2013 10:45